fix(rss): absolute item/channel links, atom self, application/xml

crates/adapters/rss/Cargo.toml

@@ -4,5 +4,8 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-rss-feed = { package = "rss", version = "2" }
+rss-feed = { package = "rss", version = "2", features = ["atom"] }
 domain = { workspace = true }
+
+[dev-dependencies]
+chrono = { workspace = true }

crates/adapters/rss/src/lib.rs

@@ -1,19 +1,30 @@
 use domain::models::DiaryEntry;
-use domain::ports::RssFeedRenderer;
+use domain::ports::{FeedChannel, RssFeedRenderer};
+use rss_feed::extension::atom::{self, AtomExtensionBuilder, Link};
 use rss_feed::{ChannelBuilder, GuidBuilder, ItemBuilder};
 
 pub struct RssAdapter {
-    feed_link: String,
+    base_url: String,
 }
 
 impl RssAdapter {
-    pub fn new(feed_link: String) -> Self {
-        Self { feed_link }
+    pub fn new(base_url: String) -> Self {
+        Self {
+            base_url: base_url.trim_end_matches('/').to_string(),
+        }
+    }
+
+    fn absolute(&self, path: &str) -> String {
+        format!("{}{}", self.base_url, path)
     }
 }
 
 impl RssFeedRenderer for RssAdapter {
-    fn render_feed(&self, entries: &[DiaryEntry], title: &str) -> Result<String, String> {
+    fn render_feed(
+        &self,
+        entries: &[DiaryEntry],
+        channel: &FeedChannel<'_>,
+    ) -> Result<String, String> {
         let items = entries
             .iter()
             .map(|e| {
@@ -37,12 +48,14 @@ impl RssFeedRenderer for RssAdapter {
                     .and_utc()
                     .format("%a, %d %b %Y %H:%M:%S +0000")
                     .to_string();
+                let link = self.absolute(&format!("/movies/{}", e.movie().id().value()));
                 let guid = GuidBuilder::default()
                     .value(e.review().id().value().to_string())
                     .permalink(false)
                     .build();
                 ItemBuilder::default()
                     .title(Some(item_title))
+                    .link(Some(link))
                     .description(Some(description))
                     .pub_date(Some(pub_date))
                     .guid(Some(guid))
@@ -50,10 +63,24 @@ impl RssFeedRenderer for RssAdapter {
             })
             .collect::<Vec<_>>();
 
+        let self_link = Link {
+            href: self.absolute(channel.self_path),
+            rel: "self".to_string(),
+            mime_type: Some("application/rss+xml".to_string()),
+            ..Default::default()
+        };
+
         let channel = ChannelBuilder::default()
-            .title(title.to_string())
-            .link(self.feed_link.clone())
-            .description(title.to_string())
+            .title(channel.title.to_string())
+            .link(self.absolute(channel.link_path))
+            .description(channel.title.to_string())
+            .language(Some("en".to_string()))
+            .namespace(("atom".to_string(), atom::NAMESPACE.to_string()))
+            .atom_ext(Some(
+                AtomExtensionBuilder::default()
+                    .links(vec![self_link])
+                    .build(),
+            ))
             .items(items)
             .build();
 

crates/adapters/rss/src/tests/lib.rs

@@ -1,15 +1,79 @@
 use super::*;
+use domain::models::{Movie, Review};
+use domain::value_objects::{Comment, MovieTitle, Rating, ReleaseYear, UserId};
+
+fn channel<'a>(title: &'a str) -> FeedChannel<'a> {
+    FeedChannel {
+        title,
+        link_path: "/users/abc",
+        self_path: "/users/abc/feed.rss",
+    }
+}
+
+fn entry(spoilers: bool) -> DiaryEntry {
+    let movie = Movie::new(
+        None,
+        MovieTitle::new("Blade Runner".into()).unwrap(),
+        ReleaseYear::new(1982).unwrap(),
+        None,
+        None,
+    );
+    let review = Review::new(
+        movie.id().clone(),
+        UserId::generate(),
+        Rating::new(4).unwrap(),
+        Some(Comment::new("replicants".into()).unwrap()),
+        chrono::Utc::now().naive_utc(),
+        None,
+        spoilers,
+    )
+    .unwrap();
+    DiaryEntry::new(movie, review)
+}
 
 #[test]
 fn render_feed_uses_provided_title() {
     let adapter = RssAdapter::new("http://example.com".into());
-    let xml = adapter.render_feed(&[], "Custom Title").unwrap();
+    let xml = adapter.render_feed(&[], &channel("Custom Title")).unwrap();
     assert!(xml.contains("<title>Custom Title</title>"));
 }
 
 #[test]
 fn render_feed_empty_entries_produces_valid_xml() {
     let adapter = RssAdapter::new("http://example.com".into());
-    let xml = adapter.render_feed(&[], "My Feed").unwrap();
+    let xml = adapter.render_feed(&[], &channel("My Feed")).unwrap();
     assert!(xml.starts_with("<?xml") || xml.starts_with("<rss"));
 }
+
+#[test]
+fn channel_links_are_absolute_with_atom_self() {
+    let adapter = RssAdapter::new("http://example.com/".into());
+    let xml = adapter.render_feed(&[], &channel("Feed")).unwrap();
+    assert!(xml.contains("<link>http://example.com/users/abc</link>"));
+    assert!(xml.contains(r#"xmlns:atom="http://www.w3.org/2005/Atom""#));
+    assert!(xml.contains(r#"href="http://example.com/users/abc/feed.rss""#));
+    assert!(xml.contains(r#"rel="self""#));
+    assert!(xml.contains("<language>en</language>"));
+}
+
+#[test]
+fn item_links_to_absolute_movie_page() {
+    let adapter = RssAdapter::new("http://example.com".into());
+    let e = entry(false);
+    let xml = adapter.render_feed(&[e.clone()], &channel("Feed")).unwrap();
+    let expected = format!(
+        "<link>http://example.com/movies/{}</link>",
+        e.movie().id().value()
+    );
+    assert!(xml.contains(&expected), "{xml}");
+}
+
+#[test]
+fn spoiler_comment_is_omitted() {
+    let adapter = RssAdapter::new("http://example.com".into());
+    let xml = adapter
+        .render_feed(&[entry(true)], &channel("Feed"))
+        .unwrap();
+    assert!(xml.contains("contains spoilers"));
+    assert!(!xml.contains("replicants"));
+}